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gerrit-public.fairphone.software / platform / external / clang / 06ddd81e137997f4a43524f204a16921efff7c8a / . / Sema / SemaExpr.cpp
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//===--- SemaExpr.cpp - Semantic Analysis for Expressions -----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Chris Lattner and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements semantic analysis for expressions.
//
//===----------------------------------------------------------------------===//
#include "Sema.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/Decl.h"
#include "clang/AST/Expr.h"
#include "clang/Lex/Preprocessor.h"
#include "clang/Lex/LiteralSupport.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Basic/Diagnostic.h"
#include "clang/Basic/LangOptions.h"
#include "clang/Basic/TargetInfo.h"
#include "llvm/ADT/SmallString.h"
using namespace clang;
/// ParseStringLiteral - The specified tokens were lexed as pasted string
/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string
/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from
/// multiple tokens. However, the common case is that StringToks points to one
/// string.
///
Action::ExprResult
Sema::ParseStringLiteral(const Token *StringToks, unsigned NumStringToks) {
assert(NumStringToks && "Must have at least one string!");
StringLiteralParser Literal(StringToks, NumStringToks, PP, Context.Target);
if (Literal.hadError)
return ExprResult(true);
llvm::SmallVector<SourceLocation, 4> StringTokLocs;
for (unsigned i = 0; i != NumStringToks; ++i)
StringTokLocs.push_back(StringToks[i].getLocation());
// FIXME: handle wchar_t
QualType t = Context.getPointerType(Context.CharTy);
// Pass &StringTokLocs[0], StringTokLocs.size() to factory!
return new StringLiteral(Literal.GetString(), Literal.GetStringLength(),
Literal.AnyWide, t, StringToks[0].getLocation(),
StringToks[NumStringToks-1].getLocation());
}
/// ParseIdentifierExpr - The parser read an identifier in expression context,
/// validate it per-C99 6.5.1. HasTrailingLParen indicates whether this
/// identifier is used in an function call context.
Sema::ExprResult Sema::ParseIdentifierExpr(Scope *S, SourceLocation Loc,
IdentifierInfo &II,
bool HasTrailingLParen) {
// Could be enum-constant or decl.
Decl *D = LookupScopedDecl(&II, Decl::IDNS_Ordinary, Loc, S);
if (D == 0) {
// Otherwise, this could be an implicitly declared function reference (legal
// in C90, extension in C99).
if (HasTrailingLParen &&
// Not in C++.
!getLangOptions().CPlusPlus)
D = ImplicitlyDefineFunction(Loc, II, S);
else {
// If this name wasn't predeclared and if this is not a function call,
// diagnose the problem.
return Diag(Loc, diag::err_undeclared_var_use, II.getName());
}
}
if (ValueDecl *VD = dyn_cast<ValueDecl>(D))
return new DeclRefExpr(VD, VD->getType(), Loc);
if (isa<TypedefDecl>(D))
return Diag(Loc, diag::err_unexpected_typedef, II.getName());
assert(0 && "Invalid decl");
abort();
}
Sema::ExprResult Sema::ParsePreDefinedExpr(SourceLocation Loc,
tok::TokenKind Kind) {
PreDefinedExpr::IdentType IT;
switch (Kind) {
default:
assert(0 && "Unknown simple primary expr!");
case tok::kw___func__: // primary-expression: __func__ [C99 6.4.2.2]
IT = PreDefinedExpr::Func;
break;
case tok::kw___FUNCTION__: // primary-expression: __FUNCTION__ [GNU]
IT = PreDefinedExpr::Function;
break;
case tok::kw___PRETTY_FUNCTION__: // primary-expression: __P..Y_F..N__ [GNU]
IT = PreDefinedExpr::PrettyFunction;
break;
}
// Pre-defined identifiers are always of type char *.
return new PreDefinedExpr(Loc, Context.getPointerType(Context.CharTy), IT);
}
Sema::ExprResult Sema::ParseCharacterConstant(const Token &Tok) {
llvm::SmallString<16> CharBuffer;
CharBuffer.resize(Tok.getLength());
const char *ThisTokBegin = &CharBuffer[0];
unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin);
CharLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength,
Tok.getLocation(), PP);
if (Literal.hadError())
return ExprResult(true);
return new CharacterLiteral(Literal.getValue(), Context.IntTy,
Tok.getLocation());
}
Action::ExprResult Sema::ParseNumericConstant(const Token &Tok) {
// fast path for a single digit (which is quite common). A single digit
// cannot have a trigraph, escaped newline, radix prefix, or type suffix.
if (Tok.getLength() == 1) {
const char *t = PP.getSourceManager().getCharacterData(Tok.getLocation());
unsigned IntSize = Context.getTypeSize(Context.IntTy, Tok.getLocation());
return ExprResult(new IntegerLiteral(llvm::APInt(IntSize, *t-'0'),
Context.IntTy,
Tok.getLocation()));
}
llvm::SmallString<512> IntegerBuffer;
IntegerBuffer.resize(Tok.getLength());
const char *ThisTokBegin = &IntegerBuffer[0];
// Get the spelling of the token, which eliminates trigraphs, etc.
unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin);
NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength,
Tok.getLocation(), PP);
if (Literal.hadError)
return ExprResult(true);
if (Literal.isIntegerLiteral()) {
QualType t;
// Get the value in the widest-possible width.
llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(Tok.getLocation()), 0);
if (Literal.GetIntegerValue(ResultVal)) {
// If this value didn't fit into uintmax_t, warn and force to ull.
Diag(Tok.getLocation(), diag::warn_integer_too_large);
t = Context.UnsignedLongLongTy;
assert(Context.getTypeSize(t, Tok.getLocation()) ==
ResultVal.getBitWidth() && "long long is not intmax_t?");
} else {
// If this value fits into a ULL, try to figure out what else it fits into
// according to the rules of C99 6.4.4.1p5.
// Octal, Hexadecimal, and integers with a U suffix are allowed to
// be an unsigned int.
bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10;
// Check from smallest to largest, picking the smallest type we can.
if (!Literal.isLong) { // Are int/unsigned possibilities?
unsigned IntSize = Context.getTypeSize(Context.IntTy,Tok.getLocation());
// Does it fit in a unsigned int?
if (ResultVal.isIntN(IntSize)) {
// Does it fit in a signed int?
if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0)
t = Context.IntTy;
else if (AllowUnsigned)
t = Context.UnsignedIntTy;
}
if (!t.isNull())
ResultVal.trunc(IntSize);
}
// Are long/unsigned long possibilities?
if (t.isNull() && !Literal.isLongLong) {
unsigned LongSize = Context.getTypeSize(Context.LongTy,
Tok.getLocation());
// Does it fit in a unsigned long?
if (ResultVal.isIntN(LongSize)) {
// Does it fit in a signed long?
if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0)
t = Context.LongTy;
else if (AllowUnsigned)
t = Context.UnsignedLongTy;
}
if (!t.isNull())
ResultVal.trunc(LongSize);
}
// Finally, check long long if needed.
if (t.isNull()) {
unsigned LongLongSize =
Context.getTypeSize(Context.LongLongTy, Tok.getLocation());
// Does it fit in a unsigned long long?
if (ResultVal.isIntN(LongLongSize)) {
// Does it fit in a signed long long?
if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0)
t = Context.LongLongTy;
else if (AllowUnsigned)
t = Context.UnsignedLongLongTy;
}
}
// If we still couldn't decide a type, we probably have something that
// does not fit in a signed long long, but has no U suffix.
if (t.isNull()) {
Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed);
t = Context.UnsignedLongLongTy;
}
}
return new IntegerLiteral(ResultVal, t, Tok.getLocation());
} else if (Literal.isFloatingLiteral()) {
// FIXME: handle float values > 32 (including compute the real type...).
return new FloatingLiteral(Literal.GetFloatValue(), Context.FloatTy,
Tok.getLocation());
}
return ExprResult(true);
}
Action::ExprResult Sema::ParseParenExpr(SourceLocation L, SourceLocation R,
ExprTy *Val) {
Expr *e = (Expr *)Val;
assert((e != 0) && "ParseParenExpr() missing expr");
return new ParenExpr(L, R, e);
}
/// The UsualUnaryConversions() function is *not* called by this routine.
/// See C99 6.3.2.1p[2-4] for more details.
QualType Sema::CheckSizeOfAlignOfOperand(QualType exprType,
SourceLocation OpLoc, bool isSizeof) {
// C99 6.5.3.4p1:
if (isa<FunctionType>(exprType) && isSizeof)
// alignof(function) is allowed.
Diag(OpLoc, diag::ext_sizeof_function_type);
else if (exprType->isVoidType())
Diag(OpLoc, diag::ext_sizeof_void_type, isSizeof ? "sizeof" : "__alignof");
else if (exprType->isIncompleteType()) {
Diag(OpLoc, isSizeof ? diag::err_sizeof_incomplete_type :
diag::err_alignof_incomplete_type,
exprType.getAsString());
return QualType(); // error
}
// C99 6.5.3.4p4: the type (an unsigned integer type) is size_t.
return Context.getSizeType();
}
Action::ExprResult Sema::
ParseSizeOfAlignOfTypeExpr(SourceLocation OpLoc, bool isSizeof,
SourceLocation LPLoc, TypeTy *Ty,
SourceLocation RPLoc) {
// If error parsing type, ignore.
if (Ty == 0) return true;
// Verify that this is a valid expression.
QualType ArgTy = QualType::getFromOpaquePtr(Ty);
QualType resultType = CheckSizeOfAlignOfOperand(ArgTy, OpLoc, isSizeof);
if (resultType.isNull())
return true;
return new SizeOfAlignOfTypeExpr(isSizeof, ArgTy, resultType, OpLoc, RPLoc);
}
Action::ExprResult Sema::ParsePostfixUnaryOp(SourceLocation OpLoc,
tok::TokenKind Kind,
ExprTy *Input) {
UnaryOperator::Opcode Opc;
switch (Kind) {
default: assert(0 && "Unknown unary op!");
case tok::plusplus: Opc = UnaryOperator::PostInc; break;
case tok::minusminus: Opc = UnaryOperator::PostDec; break;
}
QualType result = CheckIncrementDecrementOperand((Expr *)Input, OpLoc);
if (result.isNull())
return true;
return new UnaryOperator((Expr *)Input, Opc, result, OpLoc);
}
Action::ExprResult Sema::
ParseArraySubscriptExpr(ExprTy *Base, SourceLocation LLoc,
ExprTy *Idx, SourceLocation RLoc) {
Expr *LHSExp = static_cast<Expr*>(Base), *RHSExp = static_cast<Expr*>(Idx);
// Perform default conversions.
DefaultFunctionArrayConversion(LHSExp);
DefaultFunctionArrayConversion(RHSExp);
QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType();
// C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent
// to the expression *((e1)+(e2)). This means the array "Base" may actually be
// in the subscript position. As a result, we need to derive the array base
// and index from the expression types.
Expr *BaseExpr, *IndexExpr;
QualType ResultType;
if (const PointerType *PTy = LHSTy->getAsPointerType()) {
BaseExpr = LHSExp;
IndexExpr = RHSExp;
// FIXME: need to deal with const...
ResultType = PTy->getPointeeType();
} else if (const PointerType *PTy = RHSTy->getAsPointerType()) {
// Handle the uncommon case of "123[Ptr]".
BaseExpr = RHSExp;
IndexExpr = LHSExp;
// FIXME: need to deal with const...
ResultType = PTy->getPointeeType();
} else if (const VectorType *VTy = LHSTy->getAsVectorType()) {
BaseExpr = LHSExp; // vectors: V[123]
IndexExpr = RHSExp;
// FIXME: need to deal with const...
ResultType = VTy->getElementType();
} else {
return Diag(LHSExp->getLocStart(), diag::err_typecheck_subscript_value,
RHSExp->getSourceRange());
}
// C99 6.5.2.1p1
if (!IndexExpr->getType()->isIntegerType())
return Diag(IndexExpr->getLocStart(), diag::err_typecheck_subscript,
IndexExpr->getSourceRange());
// C99 6.5.2.1p1: "shall have type "pointer to *object* type". In practice,
// the following check catches trying to index a pointer to a function (e.g.
// void (*)(int)). Functions are not objects in C99.
if (!ResultType->isObjectType())
return Diag(BaseExpr->getLocStart(),
diag::err_typecheck_subscript_not_object,
BaseExpr->getType().getAsString(), BaseExpr->getSourceRange());
return new ArraySubscriptExpr(LHSExp, RHSExp, ResultType, RLoc);
}
QualType Sema::
CheckOCUVectorComponent(QualType baseType, SourceLocation OpLoc,
IdentifierInfo &CompName, SourceLocation CompLoc) {
const OCUVectorType *vecType = baseType->getAsOCUVectorType();
// The vector accessor can't exceed the number of elements.
const char *compStr = CompName.getName();
if (strlen(compStr) > vecType->getNumElements()) {
Diag(OpLoc, diag::err_ocuvector_component_exceeds_length,
baseType.getAsString(), SourceRange(CompLoc));
return QualType();
}
// The component names must come from the same set.
if (vecType->isPointAccessor(*compStr))
do { compStr++; } while (*compStr && vecType->isPointAccessor(*compStr));
else if (vecType->isColorAccessor(*compStr))
do { compStr++; } while (*compStr && vecType->isColorAccessor(*compStr));
else if (vecType->isTextureAccessor(*compStr))
do { compStr++; } while (*compStr && vecType->isTextureAccessor(*compStr));
if (*compStr) {
// We didn't get to the end of the string. This means the component names
// didn't come from the same set *or* we encountered an illegal name.
Diag(OpLoc, diag::err_ocuvector_component_name_illegal,
std::string(compStr,compStr+1), SourceRange(CompLoc));
return QualType();
}
// Each component accessor can't exceed the vector type.
compStr = CompName.getName();
while (*compStr) {
if (vecType->isAccessorWithinNumElements(*compStr))
compStr++;
else
break;
}
if (*compStr) {
// We didn't get to the end of the string. This means a component accessor
// exceeds the number of elements in the vector.
Diag(OpLoc, diag::err_ocuvector_component_exceeds_length,
baseType.getAsString(), SourceRange(CompLoc));
return QualType();
}
// The component accessor looks fine - now we need to compute the actual type.
// The vector type is implied by the component accessor. For example,
// vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc.
unsigned CompSize = strlen(CompName.getName());
if (CompSize == 1)
return vecType->getElementType();
QualType VT = Context.getOCUVectorType(vecType->getElementType(), CompSize);
// Now look up the TypeDefDecl from the vector type. Without this,
// diagostics look bad. We want OCU vector types to appear built-in.
for (unsigned i = 0, e = OCUVectorDecls.size(); i != e; ++i) {
if (OCUVectorDecls[i]->getUnderlyingType() == VT)
return Context.getTypedefType(OCUVectorDecls[i]);
}
return VT; // should never get here (a typedef type should always be found).
}
Action::ExprResult Sema::
ParseMemberReferenceExpr(ExprTy *Base, SourceLocation OpLoc,
tok::TokenKind OpKind, SourceLocation MemberLoc,
IdentifierInfo &Member) {
Expr *BaseExpr = static_cast<Expr *>(Base);
assert(BaseExpr && "no record expression");
QualType BaseType = BaseExpr->getType();
assert(!BaseType.isNull() && "no type for member expression");
if (OpKind == tok::arrow) {
if (const PointerType *PT = BaseType->getAsPointerType())
BaseType = PT->getPointeeType();
else
return Diag(OpLoc, diag::err_typecheck_member_reference_arrow,
SourceRange(MemberLoc));
}
// The base type is either a record or an OCUVectorType.
if (const RecordType *RTy = BaseType->getAsRecordType()) {
RecordDecl *RDecl = RTy->getDecl();
if (RTy->isIncompleteType())
return Diag(OpLoc, diag::err_typecheck_incomplete_tag, RDecl->getName(),
BaseExpr->getSourceRange());
// The record definition is complete, now make sure the member is valid.
FieldDecl *MemberDecl = RDecl->getMember(&Member);
if (!MemberDecl)
return Diag(OpLoc, diag::err_typecheck_no_member, Member.getName(),
SourceRange(MemberLoc));
return new MemberExpr(BaseExpr, OpKind==tok::arrow, MemberDecl, MemberLoc);
} else if (BaseType->isOCUVectorType() && OpKind == tok::period) {
QualType ret = CheckOCUVectorComponent(BaseType, OpLoc, Member, MemberLoc);
if (ret.isNull())
return true;
return new OCUVectorComponent(ret, BaseExpr, Member, MemberLoc);
} else
return Diag(OpLoc, diag::err_typecheck_member_reference_structUnion,
SourceRange(MemberLoc));
}
/// ParseCallExpr - Handle a call to Fn with the specified array of arguments.
/// This provides the location of the left/right parens and a list of comma
/// locations.
Action::ExprResult Sema::
ParseCallExpr(ExprTy *fn, SourceLocation LParenLoc,
ExprTy **args, unsigned NumArgsInCall,
SourceLocation *CommaLocs, SourceLocation RParenLoc) {
Expr *Fn = static_cast<Expr *>(fn);
Expr **Args = reinterpret_cast<Expr**>(args);
assert(Fn && "no function call expression");
UsualUnaryConversions(Fn);
QualType funcType = Fn->getType();
// C99 6.5.2.2p1 - "The expression that denotes the called function shall have
// type pointer to function".
const PointerType *PT = funcType->getAsPointerType();
if (PT == 0)
return Diag(Fn->getLocStart(), diag::err_typecheck_call_not_function,
SourceRange(Fn->getLocStart(), RParenLoc));
const FunctionType *funcT = PT->getPointeeType()->getAsFunctionType();
if (funcT == 0)
return Diag(Fn->getLocStart(), diag::err_typecheck_call_not_function,
SourceRange(Fn->getLocStart(), RParenLoc));
// If a prototype isn't declared, the parser implicitly defines a func decl
QualType resultType = funcT->getResultType();
if (const FunctionTypeProto *proto = dyn_cast<FunctionTypeProto>(funcT)) {
// C99 6.5.2.2p7 - the arguments are implicitly converted, as if by
// assignment, to the types of the corresponding parameter, ...
unsigned NumArgsInProto = proto->getNumArgs();
unsigned NumArgsToCheck = NumArgsInCall;
if (NumArgsInCall < NumArgsInProto)
Diag(RParenLoc, diag::err_typecheck_call_too_few_args,
Fn->getSourceRange());
else if (NumArgsInCall > NumArgsInProto) {
if (!proto->isVariadic()) {
Diag(Args[NumArgsInProto]->getLocStart(),
diag::err_typecheck_call_too_many_args, Fn->getSourceRange(),
SourceRange(Args[NumArgsInProto]->getLocStart(),
Args[NumArgsInCall-1]->getLocEnd()));
}
NumArgsToCheck = NumArgsInProto;
}
// Continue to check argument types (even if we have too few/many args).
for (unsigned i = 0; i < NumArgsToCheck; i++) {
Expr *argExpr = Args[i];
assert(argExpr && "ParseCallExpr(): missing argument expression");
QualType lhsType = proto->getArgType(i);
QualType rhsType = argExpr->getType();
// If necessary, apply function/array conversion. C99 6.7.5.3p[7,8].
if (const ArrayType *ary = lhsType->getAsArrayType())
lhsType = Context.getPointerType(ary->getElementType());
else if (lhsType->isFunctionType())
lhsType = Context.getPointerType(lhsType);
AssignmentCheckResult result = CheckSingleAssignmentConstraints(lhsType,
argExpr);
SourceLocation l = argExpr->getLocStart();
// decode the result (notice that AST's are still created for extensions).
switch (result) {
case Compatible:
break;
case PointerFromInt:
// check for null pointer constant (C99 6.3.2.3p3)
if (!argExpr->isNullPointerConstant(Context)) {
Diag(l, diag::ext_typecheck_passing_pointer_int,
lhsType.getAsString(), rhsType.getAsString(),
Fn->getSourceRange(), argExpr->getSourceRange());
}
break;
case IntFromPointer:
Diag(l, diag::ext_typecheck_passing_pointer_int,
lhsType.getAsString(), rhsType.getAsString(),
Fn->getSourceRange(), argExpr->getSourceRange());
break;
case IncompatiblePointer:
Diag(l, diag::ext_typecheck_passing_incompatible_pointer,
rhsType.getAsString(), lhsType.getAsString(),
Fn->getSourceRange(), argExpr->getSourceRange());
break;
case CompatiblePointerDiscardsQualifiers:
Diag(l, diag::ext_typecheck_passing_discards_qualifiers,
rhsType.getAsString(), lhsType.getAsString(),
Fn->getSourceRange(), argExpr->getSourceRange());
break;
case Incompatible:
return Diag(l, diag::err_typecheck_passing_incompatible,
rhsType.getAsString(), lhsType.getAsString(),
Fn->getSourceRange(), argExpr->getSourceRange());
}
}
// Even if the types checked, bail if we had the wrong number of arguments.
if (NumArgsInCall != NumArgsInProto && !proto->isVariadic())
return true;
}
return new CallExpr(Fn, Args, NumArgsInCall, resultType, RParenLoc);
}
Action::ExprResult Sema::
ParseCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty,
SourceLocation RParenLoc, ExprTy *InitExpr) {
assert((Ty != 0) && "ParseCompoundLiteral(): missing type");
QualType literalType = QualType::getFromOpaquePtr(Ty);
// FIXME: put back this assert when initializers are worked out.
//assert((InitExpr != 0) && "ParseCompoundLiteral(): missing expression");
Expr *literalExpr = static_cast<Expr*>(InitExpr);
// FIXME: add semantic analysis (C99 6.5.2.5).
return new CompoundLiteralExpr(literalType, literalExpr);
}
Action::ExprResult Sema::
ParseInitList(SourceLocation LParenLoc, ExprTy **InitList, unsigned NumInit,
SourceLocation RParenLoc) {
// FIXME: add semantic analysis (C99 6.7.8). This involves
// knowledge of the object being intialized. As a result, the code for
// doing the semantic analysis will likely be located elsewhere (i.e. in
// consumers of InitListExpr (e.g. ParseDeclarator, ParseCompoundLiteral).
return false; // FIXME instantiate an InitListExpr.
}
Action::ExprResult Sema::
ParseCastExpr(SourceLocation LParenLoc, TypeTy *Ty,
SourceLocation RParenLoc, ExprTy *Op) {
assert((Ty != 0) && (Op != 0) && "ParseCastExpr(): missing type or expr");
Expr *castExpr = static_cast<Expr*>(Op);
QualType castType = QualType::getFromOpaquePtr(Ty);
// C99 6.5.4p2: the cast type needs to be void or scalar and the expression
// type needs to be scalar.
if (!castType->isScalarType() && !castType->isVoidType()) {
return Diag(LParenLoc, diag::err_typecheck_cond_expect_scalar,
castType.getAsString(), SourceRange(LParenLoc, RParenLoc));
}
if (!castExpr->getType()->isScalarType()) {
return Diag(castExpr->getLocStart(),
diag::err_typecheck_expect_scalar_operand,
castExpr->getType().getAsString(), castExpr->getSourceRange());
}
return new CastExpr(castType, castExpr, LParenLoc);
}
inline QualType Sema::CheckConditionalOperands( // C99 6.5.15
Expr *&cond, Expr *&lex, Expr *&rex, SourceLocation questionLoc) {
UsualUnaryConversions(cond);
UsualUnaryConversions(lex);
UsualUnaryConversions(rex);
QualType condT = cond->getType();
QualType lexT = lex->getType();
QualType rexT = rex->getType();
// first, check the condition.
if (!condT->isScalarType()) { // C99 6.5.15p2
Diag(cond->getLocStart(), diag::err_typecheck_cond_expect_scalar,
condT.getAsString());
return QualType();
}
// now check the two expressions.
if (lexT->isArithmeticType() && rexT->isArithmeticType()) { // C99 6.5.15p3,5
UsualArithmeticConversions(lex, rex);
return lex->getType();
}
if (const RecordType *LHSRT = lexT->getAsRecordType()) { // C99 6.5.15p3
if (const RecordType *RHSRT = rexT->getAsRecordType()) {
if (LHSRT->getDecl()->getIdentifier() ==RHSRT->getDecl()->getIdentifier())
return lexT;
Diag(questionLoc, diag::err_typecheck_cond_incompatible_operands,
lexT.getAsString(), rexT.getAsString(),
lex->getSourceRange(), rex->getSourceRange());
return QualType();
}
}
// C99 6.5.15p3
if (lexT->isPointerType() && rex->isNullPointerConstant(Context))
return lexT;
if (rexT->isPointerType() && lex->isNullPointerConstant(Context))
return rexT;
if (const PointerType *LHSPT = lexT->getAsPointerType()) { // C99 6.5.15p3,6
if (const PointerType *RHSPT = rexT->getAsPointerType()) {
// get the "pointed to" types
QualType lhptee = LHSPT->getPointeeType();
QualType rhptee = RHSPT->getPointeeType();
// ignore qualifiers on void (C99 6.5.15p3, clause 6)
if (lhptee->isVoidType() &&
(rhptee->isObjectType() || rhptee->isIncompleteType()))
return lexT;
if (rhptee->isVoidType() &&
(lhptee->isObjectType() || lhptee->isIncompleteType()))
return rexT;
if (!Type::typesAreCompatible(lhptee.getUnqualifiedType(),
rhptee.getUnqualifiedType())) {
Diag(questionLoc, diag::ext_typecheck_cond_incompatible_pointers,
lexT.getAsString(), rexT.getAsString(),
lex->getSourceRange(), rex->getSourceRange());
return lexT; // FIXME: this is an _ext - is this return o.k?
}
// The pointer types are compatible.
// C99 6.5.15p6: If both operands are pointers to compatible types *or* to
// differently qualified versions of compatible types, the result type is a
// pointer to an appropriately qualified version of the *composite* type.
return lexT; // FIXME: Need to return the composite type.
}
}
if (lexT->isVoidType() && rexT->isVoidType()) // C99 6.5.15p3
return lexT;
Diag(questionLoc, diag::err_typecheck_cond_incompatible_operands,
lexT.getAsString(), rexT.getAsString(),
lex->getSourceRange(), rex->getSourceRange());
return QualType();
}
/// ParseConditionalOp - Parse a ?: operation. Note that 'LHS' may be null
/// in the case of a the GNU conditional expr extension.
Action::ExprResult Sema::ParseConditionalOp(SourceLocation QuestionLoc,
SourceLocation ColonLoc,
ExprTy *Cond, ExprTy *LHS,
ExprTy *RHS) {
Expr *CondExpr = (Expr *) Cond;
Expr *LHSExpr = (Expr *) LHS, *RHSExpr = (Expr *) RHS;
QualType result = CheckConditionalOperands(CondExpr, LHSExpr,
RHSExpr, QuestionLoc);
if (result.isNull())
return true;
return new ConditionalOperator(CondExpr, LHSExpr, RHSExpr, result);
}
// promoteExprToType - a helper function to ensure we create exactly one
// ImplicitCastExpr. As a convenience (to the caller), we return the type.
static void promoteExprToType(Expr *&expr, QualType type) {
if (ImplicitCastExpr *impCast = dyn_cast<ImplicitCastExpr>(expr))
impCast->setType(type);
else
expr = new ImplicitCastExpr(type, expr);
return;
}
/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4).
void Sema::DefaultFunctionArrayConversion(Expr *&e) {
QualType t = e->getType();
assert(!t.isNull() && "DefaultFunctionArrayConversion - missing type");
if (const ReferenceType *ref = t->getAsReferenceType()) {
promoteExprToType(e, ref->getReferenceeType()); // C++ [expr]
t = e->getType();
}
if (t->isFunctionType())
promoteExprToType(e, Context.getPointerType(t));
else if (const ArrayType *ary = t->getAsArrayType())
promoteExprToType(e, Context.getPointerType(ary->getElementType()));
}
/// UsualUnaryConversion - Performs various conversions that are common to most
/// operators (C99 6.3). The conversions of array and function types are
/// sometimes surpressed. For example, the array->pointer conversion doesn't
/// apply if the array is an argument to the sizeof or address (&) operators.
/// In these instances, this routine should *not* be called.
void Sema::UsualUnaryConversions(Expr *&expr) {
QualType t = expr->getType();
assert(!t.isNull() && "UsualUnaryConversions - missing type");
if (const ReferenceType *ref = t->getAsReferenceType()) {
promoteExprToType(expr, ref->getReferenceeType()); // C++ [expr]
t = expr->getType();
}
if (t->isPromotableIntegerType()) // C99 6.3.1.1p2
promoteExprToType(expr, Context.IntTy);
else
DefaultFunctionArrayConversion(expr);
}
/// UsualArithmeticConversions - Performs various conversions that are common to
/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this
/// routine returns the first non-arithmetic type found. The client is
/// responsible for emitting appropriate error diagnostics.
void Sema::UsualArithmeticConversions(Expr *&lhsExpr, Expr *&rhsExpr) {
UsualUnaryConversions(lhsExpr);
UsualUnaryConversions(rhsExpr);
QualType lhs = lhsExpr->getType();
QualType rhs = rhsExpr->getType();
// If both types are identical, no conversion is needed.
if (lhs == rhs)
return;
// If either side is a non-arithmetic type (e.g. a pointer), we are done.
// The caller can deal with this (e.g. pointer + int).
if (!lhs->isArithmeticType() || !rhs->isArithmeticType())
return;
// At this point, we have two different arithmetic types.
// Handle complex types first (C99 6.3.1.8p1).
if (lhs->isComplexType() || rhs->isComplexType()) {
// if we have an integer operand, the result is the complex type.
if (rhs->isIntegerType()) { // convert the rhs to the lhs complex type.
promoteExprToType(rhsExpr, lhs);
return;
}
if (lhs->isIntegerType()) { // convert the lhs to the rhs complex type.
promoteExprToType(lhsExpr, rhs);
return;
}
// Two complex types. Convert the smaller operand to the bigger result.
if (Context.maxComplexType(lhs, rhs) == lhs) { // convert the rhs
promoteExprToType(rhsExpr, lhs);
return;
}
promoteExprToType(lhsExpr, rhs); // convert the lhs
return;
}
// Now handle "real" floating types (i.e. float, double, long double).
if (lhs->isRealFloatingType() || rhs->isRealFloatingType()) {
// if we have an integer operand, the result is the real floating type.
if (rhs->isIntegerType()) { // convert rhs to the lhs floating point type.
promoteExprToType(rhsExpr, lhs);
return;
}
if (lhs->isIntegerType()) { // convert lhs to the rhs floating point type.
promoteExprToType(lhsExpr, rhs);
return;
}
// We have two real floating types, float/complex combos were handled above.
// Convert the smaller operand to the bigger result.
if (Context.maxFloatingType(lhs, rhs) == lhs) { // convert the rhs
promoteExprToType(rhsExpr, lhs);
return;
}
promoteExprToType(lhsExpr, rhs); // convert the lhs
return;
}
// Finally, we have two differing integer types.
if (Context.maxIntegerType(lhs, rhs) == lhs) { // convert the rhs
promoteExprToType(rhsExpr, lhs);
return;
}
promoteExprToType(lhsExpr, rhs); // convert the lhs
return;
}
// CheckPointerTypesForAssignment - This is a very tricky routine (despite
// being closely modeled after the C99 spec:-). The odd characteristic of this
// routine is it effectively iqnores the qualifiers on the top level pointee.
// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3].
// FIXME: add a couple examples in this comment.
Sema::AssignmentCheckResult
Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) {
QualType lhptee, rhptee;
// get the "pointed to" type (ignoring qualifiers at the top level)
lhptee = lhsType->getAsPointerType()->getPointeeType();
rhptee = rhsType->getAsPointerType()->getPointeeType();
// make sure we operate on the canonical type
lhptee = lhptee.getCanonicalType();
rhptee = rhptee.getCanonicalType();
AssignmentCheckResult r = Compatible;
// C99 6.5.16.1p1: This following citation is common to constraints
// 3 & 4 (below). ...and the type *pointed to* by the left has all the
// qualifiers of the type *pointed to* by the right;
if ((lhptee.getQualifiers() & rhptee.getQualifiers()) !=
rhptee.getQualifiers())
r = CompatiblePointerDiscardsQualifiers;
// C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or
// incomplete type and the other is a pointer to a qualified or unqualified
// version of void...
if (lhptee.getUnqualifiedType()->isVoidType() &&
(rhptee->isObjectType() || rhptee->isIncompleteType()))
;
else if (rhptee.getUnqualifiedType()->isVoidType() &&
(lhptee->isObjectType() || lhptee->isIncompleteType()))
;
// C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or
// unqualified versions of compatible types, ...
else if (!Type::typesAreCompatible(lhptee.getUnqualifiedType(),
rhptee.getUnqualifiedType()))
r = IncompatiblePointer; // this "trumps" PointerAssignDiscardsQualifiers
return r;
}
/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently
/// has code to accommodate several GCC extensions when type checking
/// pointers. Here are some objectionable examples that GCC considers warnings:
///
/// int a, *pint;
/// short *pshort;
/// struct foo *pfoo;
///
/// pint = pshort; // warning: assignment from incompatible pointer type
/// a = pint; // warning: assignment makes integer from pointer without a cast
/// pint = a; // warning: assignment makes pointer from integer without a cast
/// pint = pfoo; // warning: assignment from incompatible pointer type
///
/// As a result, the code for dealing with pointers is more complex than the
/// C99 spec dictates.
/// Note: the warning above turn into errors when -pedantic-errors is enabled.
///
Sema::AssignmentCheckResult
Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) {
if (lhsType == rhsType) // common case, fast path...
return Compatible;
if (lhsType->isArithmeticType() && rhsType->isArithmeticType()) {
if (lhsType->isVectorType() || rhsType->isVectorType()) {
if (lhsType.getCanonicalType() != rhsType.getCanonicalType())
return Incompatible;
}
return Compatible;
} else if (lhsType->isPointerType()) {
if (rhsType->isIntegerType())
return PointerFromInt;
if (rhsType->isPointerType())
return CheckPointerTypesForAssignment(lhsType, rhsType);
} else if (rhsType->isPointerType()) {
// C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer.
if ((lhsType->isIntegerType()) && (lhsType != Context.BoolTy))
return IntFromPointer;
if (lhsType->isPointerType())
return CheckPointerTypesForAssignment(lhsType, rhsType);
} else if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) {
if (Type::tagTypesAreCompatible(lhsType, rhsType))
return Compatible;
} else if (lhsType->isReferenceType() || rhsType->isReferenceType()) {
if (Type::referenceTypesAreCompatible(lhsType, rhsType))
return Compatible;
}
return Incompatible;
}
Sema::AssignmentCheckResult
Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) {
// This check seems unnatural, however it is necessary to insure the proper
// conversion of functions/arrays. If the conversion were done for all
// DeclExpr's (created by ParseIdentifierExpr), it would mess up the unary
// expressions that surpress this implicit conversion (&, sizeof).
DefaultFunctionArrayConversion(rExpr);
return CheckAssignmentConstraints(lhsType, rExpr->getType());
}
Sema::AssignmentCheckResult
Sema::CheckCompoundAssignmentConstraints(QualType lhsType, QualType rhsType) {
return CheckAssignmentConstraints(lhsType, rhsType);
}
inline void Sema::InvalidOperands(SourceLocation loc, Expr *&lex, Expr *&rex) {
Diag(loc, diag::err_typecheck_invalid_operands,
lex->getType().getAsString(), rex->getType().getAsString(),
lex->getSourceRange(), rex->getSourceRange());
}
inline QualType Sema::CheckVectorOperands(SourceLocation loc, Expr *&lex,
Expr *&rex) {
QualType lhsType = lex->getType(), rhsType = rex->getType();
// make sure the vector types are identical.
if (lhsType == rhsType)
return lhsType;
// You cannot convert between vector values of different size.
Diag(loc, diag::err_typecheck_vector_not_convertable,
lex->getType().getAsString(), rex->getType().getAsString(),
lex->getSourceRange(), rex->getSourceRange());
return QualType();
}
inline QualType Sema::CheckMultiplyDivideOperands(
Expr *&lex, Expr *&rex, SourceLocation loc)
{
QualType lhsType = lex->getType(), rhsType = rex->getType();
if (lhsType->isVectorType() || rhsType->isVectorType())
return CheckVectorOperands(loc, lex, rex);
UsualArithmeticConversions(lex, rex);
// handle the common case first (both operands are arithmetic).
if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType())
return lex->getType();
InvalidOperands(loc, lex, rex);
return QualType();
}
inline QualType Sema::CheckRemainderOperands(
Expr *&lex, Expr *&rex, SourceLocation loc)
{
QualType lhsType = lex->getType(), rhsType = rex->getType();
UsualArithmeticConversions(lex, rex);
// handle the common case first (both operands are arithmetic).
if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType())
return lex->getType();
InvalidOperands(loc, lex, rex);
return QualType();
}
inline QualType Sema::CheckAdditionOperands( // C99 6.5.6
Expr *&lex, Expr *&rex, SourceLocation loc)
{
if (lex->getType()->isVectorType() || rex->getType()->isVectorType())
return CheckVectorOperands(loc, lex, rex);
UsualArithmeticConversions(lex, rex);
// handle the common case first (both operands are arithmetic).
if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType())
return lex->getType();
if (lex->getType()->isPointerType() && rex->getType()->isIntegerType())
return lex->getType();
if (lex->getType()->isIntegerType() && rex->getType()->isPointerType())
return rex->getType();
InvalidOperands(loc, lex, rex);
return QualType();
}
inline QualType Sema::CheckSubtractionOperands( // C99 6.5.6
Expr *&lex, Expr *&rex, SourceLocation loc)
{
if (lex->getType()->isVectorType() || rex->getType()->isVectorType())
return CheckVectorOperands(loc, lex, rex);
UsualArithmeticConversions(lex, rex);
// handle the common case first (both operands are arithmetic).
if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType())
return lex->getType();
if (lex->getType()->isPointerType() && rex->getType()->isIntegerType())
return lex->getType();
if (lex->getType()->isPointerType() && rex->getType()->isPointerType())
return Context.getPointerDiffType();
InvalidOperands(loc, lex, rex);
return QualType();
}
inline QualType Sema::CheckShiftOperands( // C99 6.5.7
Expr *&lex, Expr *&rex, SourceLocation loc)
{
// FIXME: Shifts don't perform usual arithmetic conversions. This is wrong
// for int << longlong -> the result type should be int, not long long.
UsualArithmeticConversions(lex, rex);
// handle the common case first (both operands are arithmetic).
if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType())
return lex->getType();
InvalidOperands(loc, lex, rex);
return QualType();
}
inline QualType Sema::CheckRelationalOperands( // C99 6.5.8
Expr *&lex, Expr *&rex, SourceLocation loc)
{
UsualUnaryConversions(lex);
UsualUnaryConversions(rex);
QualType lType = lex->getType();
QualType rType = rex->getType();
if (lType->isRealType() && rType->isRealType())
return Context.IntTy;
if (lType->isPointerType()) {
if (rType->isPointerType())
return Context.IntTy;
if (rType->isIntegerType()) {
if (!rex->isNullPointerConstant(Context))
Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer,
lex->getSourceRange(), rex->getSourceRange());
return Context.IntTy; // the previous diagnostic is a GCC extension.
}
} else if (rType->isPointerType()) {
if (lType->isIntegerType()) {
if (!lex->isNullPointerConstant(Context))
Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer,
lex->getSourceRange(), rex->getSourceRange());
return Context.IntTy; // the previous diagnostic is a GCC extension.
}
}
InvalidOperands(loc, lex, rex);
return QualType();
}
inline QualType Sema::CheckEqualityOperands( // C99 6.5.9
Expr *&lex, Expr *&rex, SourceLocation loc)
{
UsualUnaryConversions(lex);
UsualUnaryConversions(rex);
QualType lType = lex->getType();
QualType rType = rex->getType();
if (lType->isArithmeticType() && rType->isArithmeticType())
return Context.IntTy;
if (lType->isPointerType()) {
if (rType->isPointerType())
return Context.IntTy;
if (rType->isIntegerType()) {
if (!rex->isNullPointerConstant(Context))
Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer,
lex->getSourceRange(), rex->getSourceRange());
return Context.IntTy; // the previous diagnostic is a GCC extension.
}
} else if (rType->isPointerType()) {
if (lType->isIntegerType()) {
if (!lex->isNullPointerConstant(Context))
Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer,
lex->getSourceRange(), rex->getSourceRange());
return Context.IntTy; // the previous diagnostic is a GCC extension.
}
}
InvalidOperands(loc, lex, rex);
return QualType();
}
inline QualType Sema::CheckBitwiseOperands(
Expr *&lex, Expr *&rex, SourceLocation loc)
{
if (lex->getType()->isVectorType() || rex->getType()->isVectorType())
return CheckVectorOperands(loc, lex, rex);
UsualArithmeticConversions(lex, rex);
if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType())
return lex->getType();
InvalidOperands(loc, lex, rex);
return QualType();
}
inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14]
Expr *&lex, Expr *&rex, SourceLocation loc)
{
UsualUnaryConversions(lex);
UsualUnaryConversions(rex);
if (lex->getType()->isScalarType() || rex->getType()->isScalarType())
return Context.IntTy;
InvalidOperands(loc, lex, rex);
return QualType();
}
inline QualType Sema::CheckAssignmentOperands( // C99 6.5.16.1
Expr *lex, Expr *rex, SourceLocation loc, QualType compoundType)
{
QualType lhsType = lex->getType();
QualType rhsType = compoundType.isNull() ? rex->getType() : compoundType;
bool hadError = false;
Expr::isModifiableLvalueResult mlval = lex->isModifiableLvalue();
switch (mlval) { // C99 6.5.16p2
case Expr::MLV_Valid:
break;
case Expr::MLV_ConstQualified:
Diag(loc, diag::err_typecheck_assign_const, lex->getSourceRange());
hadError = true;
break;
case Expr::MLV_ArrayType:
Diag(loc, diag::err_typecheck_array_not_modifiable_lvalue,
lhsType.getAsString(), lex->getSourceRange());
return QualType();
case Expr::MLV_NotObjectType:
Diag(loc, diag::err_typecheck_non_object_not_modifiable_lvalue,
lhsType.getAsString(), lex->getSourceRange());
return QualType();
case Expr::MLV_InvalidExpression:
Diag(loc, diag::err_typecheck_expression_not_modifiable_lvalue,
lex->getSourceRange());
return QualType();
case Expr::MLV_IncompleteType:
case Expr::MLV_IncompleteVoidType:
Diag(loc, diag::err_typecheck_incomplete_type_not_modifiable_lvalue,
lhsType.getAsString(), lex->getSourceRange());
return QualType();
case Expr::MLV_DuplicateVectorComponents:
Diag(loc, diag::err_typecheck_duplicate_vector_components_not_mlvalue,
lex->getSourceRange());
return QualType();
}
AssignmentCheckResult result;
if (compoundType.isNull())
result = CheckSingleAssignmentConstraints(lhsType, rex);
else
result = CheckCompoundAssignmentConstraints(lhsType, rhsType);
// decode the result (notice that extensions still return a type).
switch (result) {
case Compatible:
break;
case Incompatible:
Diag(loc, diag::err_typecheck_assign_incompatible,
lhsType.getAsString(), rhsType.getAsString(),
lex->getSourceRange(), rex->getSourceRange());
hadError = true;
break;
case PointerFromInt:
// check for null pointer constant (C99 6.3.2.3p3)
if (compoundType.isNull() && !rex->isNullPointerConstant(Context)) {
Diag(loc, diag::ext_typecheck_assign_pointer_int,
lhsType.getAsString(), rhsType.getAsString(),
lex->getSourceRange(), rex->getSourceRange());
}
break;
case IntFromPointer:
Diag(loc, diag::ext_typecheck_assign_pointer_int,
lhsType.getAsString(), rhsType.getAsString(),
lex->getSourceRange(), rex->getSourceRange());
break;
case IncompatiblePointer:
Diag(loc, diag::ext_typecheck_assign_incompatible_pointer,
lhsType.getAsString(), rhsType.getAsString(),
lex->getSourceRange(), rex->getSourceRange());
break;
case CompatiblePointerDiscardsQualifiers:
Diag(loc, diag::ext_typecheck_assign_discards_qualifiers,
lhsType.getAsString(), rhsType.getAsString(),
lex->getSourceRange(), rex->getSourceRange());
break;
}
// C99 6.5.16p3: The type of an assignment expression is the type of the
// left operand unless the left operand has qualified type, in which case
// it is the unqualified version of the type of the left operand.
// C99 6.5.16.1p2: In simple assignment, the value of the right operand
// is converted to the type of the assignment expression (above).
// C++ 5.17p1: the type of the assignment expression is that of its left oprdu.
return hadError ? QualType() : lhsType.getUnqualifiedType();
}
inline QualType Sema::CheckCommaOperands( // C99 6.5.17
Expr *&lex, Expr *&rex, SourceLocation loc) {
UsualUnaryConversions(rex);
return rex->getType();
}
/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine
/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions.
QualType Sema::CheckIncrementDecrementOperand(Expr *op, SourceLocation OpLoc) {
QualType resType = op->getType();
assert(!resType.isNull() && "no type for increment/decrement expression");
// C99 6.5.2.4p1
if (const PointerType *pt = dyn_cast<PointerType>(resType)) {
if (!pt->getPointeeType()->isObjectType()) { // C99 6.5.2.4p2, 6.5.6p2
Diag(OpLoc, diag::err_typecheck_arithmetic_incomplete_type,
resType.getAsString(), op->getSourceRange());
return QualType();
}
} else if (!resType->isRealType()) {
// FIXME: Allow Complex as a GCC extension.
Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement,
resType.getAsString(), op->getSourceRange());
return QualType();
}
// At this point, we know we have a real or pointer type. Now make sure
// the operand is a modifiable lvalue.
Expr::isModifiableLvalueResult mlval = op->isModifiableLvalue();
if (mlval != Expr::MLV_Valid) {
// FIXME: emit a more precise diagnostic...
Diag(OpLoc, diag::err_typecheck_invalid_lvalue_incr_decr,
op->getSourceRange());
return QualType();
}
return resType;
}
/// getPrimaryDeclaration - Helper function for CheckAddressOfOperand().
/// This routine allows us to typecheck complex/recursive expressions
/// where the declaration is needed for type checking. Here are some
/// examples: &s.xx, &s.zz[1].yy, &(1+2), &(XX), &"123"[2].
static Decl *getPrimaryDeclaration(Expr *e) {
switch (e->getStmtClass()) {
case Stmt::DeclRefExprClass:
return cast<DeclRefExpr>(e)->getDecl();
case Stmt::MemberExprClass:
return getPrimaryDeclaration(cast<MemberExpr>(e)->getBase());
case Stmt::ArraySubscriptExprClass:
return getPrimaryDeclaration(cast<ArraySubscriptExpr>(e)->getBase());
case Stmt::CallExprClass:
return getPrimaryDeclaration(cast<CallExpr>(e)->getCallee());
case Stmt::UnaryOperatorClass:
return getPrimaryDeclaration(cast<UnaryOperator>(e)->getSubExpr());
case Stmt::ParenExprClass:
return getPrimaryDeclaration(cast<ParenExpr>(e)->getSubExpr());
default:
return 0;
}
}
/// CheckAddressOfOperand - The operand of & must be either a function
/// designator or an lvalue designating an object. If it is an lvalue, the
/// object cannot be declared with storage class register or be a bit field.
/// Note: The usual conversions are *not* applied to the operand of the &
/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue.
QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) {
Decl *dcl = getPrimaryDeclaration(op);
Expr::isLvalueResult lval = op->isLvalue();
if (lval != Expr::LV_Valid) { // C99 6.5.3.2p1
if (dcl && isa<FunctionDecl>(dcl)) // allow function designators
;
else { // FIXME: emit more specific diag...
Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof,
op->getSourceRange());
return QualType();
}
} else if (dcl) {
// We have an lvalue with a decl. Make sure the decl is not declared
// with the register storage-class specifier.
if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) {
if (vd->getStorageClass() == VarDecl::Register) {
Diag(OpLoc, diag::err_typecheck_address_of_register,
op->getSourceRange());
return QualType();
}
} else
assert(0 && "Unknown/unexpected decl type");
// FIXME: add check for bitfields!
}
// If the operand has type "type", the result has type "pointer to type".
return Context.getPointerType(op->getType());
}
QualType Sema::CheckIndirectionOperand(Expr *op, SourceLocation OpLoc) {
UsualUnaryConversions(op);
QualType qType = op->getType();
if (const PointerType *PT = qType->getAsPointerType()) {
QualType ptype = PT->getPointeeType();
// C99 6.5.3.2p4. "if it points to an object,...".
if (ptype->isIncompleteType()) { // An incomplete type is not an object
// GCC compat: special case 'void *' (treat as warning).
if (ptype->isVoidType()) {
Diag(OpLoc, diag::ext_typecheck_deref_ptr_to_void,
qType.getAsString(), op->getSourceRange());
} else {
Diag(OpLoc, diag::err_typecheck_deref_incomplete_type,
ptype.getAsString(), op->getSourceRange());
return QualType();
}
}
return ptype;
}
Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer,
qType.getAsString(), op->getSourceRange());
return QualType();
}
static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode(
tok::TokenKind Kind) {
BinaryOperator::Opcode Opc;
switch (Kind) {
default: assert(0 && "Unknown binop!");
case tok::star: Opc = BinaryOperator::Mul; break;
case tok::slash: Opc = BinaryOperator::Div; break;
case tok::percent: Opc = BinaryOperator::Rem; break;
case tok::plus: Opc = BinaryOperator::Add; break;
case tok::minus: Opc = BinaryOperator::Sub; break;
case tok::lessless: Opc = BinaryOperator::Shl; break;
case tok::greatergreater: Opc = BinaryOperator::Shr; break;
case tok::lessequal: Opc = BinaryOperator::LE; break;
case tok::less: Opc = BinaryOperator::LT; break;
case tok::greaterequal: Opc = BinaryOperator::GE; break;
case tok::greater: Opc = BinaryOperator::GT; break;
case tok::exclaimequal: Opc = BinaryOperator::NE; break;
case tok::equalequal: Opc = BinaryOperator::EQ; break;
case tok::amp: Opc = BinaryOperator::And; break;
case tok::caret: Opc = BinaryOperator::Xor; break;
case tok::pipe: Opc = BinaryOperator::Or; break;
case tok::ampamp: Opc = BinaryOperator::LAnd; break;
case tok::pipepipe: Opc = BinaryOperator::LOr; break;
case tok::equal: Opc = BinaryOperator::Assign; break;
case tok::starequal: Opc = BinaryOperator::MulAssign; break;
case tok::slashequal: Opc = BinaryOperator::DivAssign; break;
case tok::percentequal: Opc = BinaryOperator::RemAssign; break;
case tok::plusequal: Opc = BinaryOperator::AddAssign; break;
case tok::minusequal: Opc = BinaryOperator::SubAssign; break;
case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break;
case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break;
case tok::ampequal: Opc = BinaryOperator::AndAssign; break;
case tok::caretequal: Opc = BinaryOperator::XorAssign; break;
case tok::pipeequal: Opc = BinaryOperator::OrAssign; break;
case tok::comma: Opc = BinaryOperator::Comma; break;
}
return Opc;
}
static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode(
tok::TokenKind Kind) {
UnaryOperator::Opcode Opc;
switch (Kind) {
default: assert(0 && "Unknown unary op!");
case tok::plusplus: Opc = UnaryOperator::PreInc; break;
case tok::minusminus: Opc = UnaryOperator::PreDec; break;
case tok::amp: Opc = UnaryOperator::AddrOf; break;
case tok::star: Opc = UnaryOperator::Deref; break;
case tok::plus: Opc = UnaryOperator::Plus; break;
case tok::minus: Opc = UnaryOperator::Minus; break;
case tok::tilde: Opc = UnaryOperator::Not; break;
case tok::exclaim: Opc = UnaryOperator::LNot; break;
case tok::kw_sizeof: Opc = UnaryOperator::SizeOf; break;
case tok::kw___alignof: Opc = UnaryOperator::AlignOf; break;
case tok::kw___real: Opc = UnaryOperator::Real; break;
case tok::kw___imag: Opc = UnaryOperator::Imag; break;
case tok::kw___extension__: Opc = UnaryOperator::Extension; break;
}
return Opc;
}
// Binary Operators. 'Tok' is the token for the operator.
Action::ExprResult Sema::ParseBinOp(SourceLocation TokLoc, tok::TokenKind Kind,
ExprTy *LHS, ExprTy *RHS) {
BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind);
Expr *lhs = (Expr *)LHS, *rhs = (Expr*)RHS;
assert((lhs != 0) && "ParseBinOp(): missing left expression");
assert((rhs != 0) && "ParseBinOp(): missing right expression");
QualType ResultTy; // Result type of the binary operator.
QualType CompTy; // Computation type for compound assignments (e.g. '+=')
switch (Opc) {
default:
assert(0 && "Unknown binary expr!");
case BinaryOperator::Assign:
ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, QualType());
break;
case BinaryOperator::Mul:
case BinaryOperator::Div:
ResultTy = CheckMultiplyDivideOperands(lhs, rhs, TokLoc);
break;
case BinaryOperator::Rem:
ResultTy = CheckRemainderOperands(lhs, rhs, TokLoc);
break;
case BinaryOperator::Add:
ResultTy = CheckAdditionOperands(lhs, rhs, TokLoc);
break;
case BinaryOperator::Sub:
ResultTy = CheckSubtractionOperands(lhs, rhs, TokLoc);
break;
case BinaryOperator::Shl:
case BinaryOperator::Shr:
ResultTy = CheckShiftOperands(lhs, rhs, TokLoc);
break;
case BinaryOperator::LE:
case BinaryOperator::LT:
case BinaryOperator::GE:
case BinaryOperator::GT:
ResultTy = CheckRelationalOperands(lhs, rhs, TokLoc);
break;
case BinaryOperator::EQ:
case BinaryOperator::NE:
ResultTy = CheckEqualityOperands(lhs, rhs, TokLoc);
break;
case BinaryOperator::And:
case BinaryOperator::Xor:
case BinaryOperator::Or:
ResultTy = CheckBitwiseOperands(lhs, rhs, TokLoc);
break;
case BinaryOperator::LAnd:
case BinaryOperator::LOr:
ResultTy = CheckLogicalOperands(lhs, rhs, TokLoc);
break;
case BinaryOperator::MulAssign:
case BinaryOperator::DivAssign:
CompTy = CheckMultiplyDivideOperands(lhs, rhs, TokLoc);
if (!CompTy.isNull())
ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy);
break;
case BinaryOperator::RemAssign:
CompTy = CheckRemainderOperands(lhs, rhs, TokLoc);
if (!CompTy.isNull())
ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy);
break;
case BinaryOperator::AddAssign:
CompTy = CheckAdditionOperands(lhs, rhs, TokLoc);
if (!CompTy.isNull())
ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy);
break;
case BinaryOperator::SubAssign:
CompTy = CheckSubtractionOperands(lhs, rhs, TokLoc);
if (!CompTy.isNull())
ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy);
break;
case BinaryOperator::ShlAssign:
case BinaryOperator::ShrAssign:
CompTy = CheckShiftOperands(lhs, rhs, TokLoc);
if (!CompTy.isNull())
ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy);
break;
case BinaryOperator::AndAssign:
case BinaryOperator::XorAssign:
case BinaryOperator::OrAssign:
CompTy = CheckBitwiseOperands(lhs, rhs, TokLoc);
if (!CompTy.isNull())
ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy);
break;
case BinaryOperator::Comma:
ResultTy = CheckCommaOperands(lhs, rhs, TokLoc);
break;
}
if (ResultTy.isNull())
return true;
if (CompTy.isNull())
return new BinaryOperator(lhs, rhs, Opc, ResultTy);
else
return new CompoundAssignOperator(lhs, rhs, Opc, ResultTy, CompTy);
}
// Unary Operators. 'Tok' is the token for the operator.
Action::ExprResult Sema::ParseUnaryOp(SourceLocation OpLoc, tok::TokenKind Op,
ExprTy *input) {
Expr *Input = (Expr*)input;
UnaryOperator::Opcode Opc = ConvertTokenKindToUnaryOpcode(Op);
QualType resultType;
switch (Opc) {
default:
assert(0 && "Unimplemented unary expr!");
case UnaryOperator::PreInc:
case UnaryOperator::PreDec:
resultType = CheckIncrementDecrementOperand(Input, OpLoc);
break;
case UnaryOperator::AddrOf:
resultType = CheckAddressOfOperand(Input, OpLoc);
break;
case UnaryOperator::Deref:
resultType = CheckIndirectionOperand(Input, OpLoc);
break;
case UnaryOperator::Plus:
case UnaryOperator::Minus:
UsualUnaryConversions(Input);
resultType = Input->getType();
if (!resultType->isArithmeticType()) // C99 6.5.3.3p1
return Diag(OpLoc, diag::err_typecheck_unary_expr,
resultType.getAsString());
break;
case UnaryOperator::Not: // bitwise complement
UsualUnaryConversions(Input);
resultType = Input->getType();
if (!resultType->isIntegerType()) // C99 6.5.3.3p1
return Diag(OpLoc, diag::err_typecheck_unary_expr,
resultType.getAsString());
break;
case UnaryOperator::LNot: // logical negation
// Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5).
DefaultFunctionArrayConversion(Input);
resultType = Input->getType();
if (!resultType->isScalarType()) // C99 6.5.3.3p1
return Diag(OpLoc, diag::err_typecheck_unary_expr,
resultType.getAsString());
// LNot always has type int. C99 6.5.3.3p5.
resultType = Context.IntTy;
break;
case UnaryOperator::SizeOf:
resultType = CheckSizeOfAlignOfOperand(Input->getType(), OpLoc, true);
break;
case UnaryOperator::AlignOf:
resultType = CheckSizeOfAlignOfOperand(Input->getType(), OpLoc, false);
break;
case UnaryOperator::Extension:
// FIXME: does __extension__ cause any promotions? I would think not.
resultType = Input->getType();
break;
}
if (resultType.isNull())
return true;
return new UnaryOperator(Input, Opc, resultType, OpLoc);
}
/// ParseAddrLabel - Parse the GNU address of label extension: "&&foo".
Sema::ExprResult Sema::ParseAddrLabel(SourceLocation OpLoc,
SourceLocation LabLoc,
IdentifierInfo *LabelII) {
// Look up the record for this label identifier.
LabelStmt *&LabelDecl = LabelMap[LabelII];
// If we haven't seen this label yet, create a forward reference.
if (LabelDecl == 0)
LabelDecl = new LabelStmt(LabLoc, LabelII, 0);
// Create the AST node. The address of a label always has type 'void*'.
return new AddrLabel(OpLoc, LabLoc, LabelDecl,
Context.getPointerType(Context.VoidTy));
}
Sema::ExprResult Sema::ParseStmtExpr(SourceLocation LPLoc, StmtTy *substmt,
SourceLocation RPLoc) { // "({..})"
Stmt *SubStmt = static_cast<Stmt*>(substmt);
assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!");
CompoundStmt *Compound = cast<CompoundStmt>(SubStmt);
// FIXME: there are a variety of strange constraints to enforce here, for
// example, it is not possible to goto into a stmt expression apparently.
// More semantic analysis is needed.
// FIXME: the last statement in the compount stmt has its value used. We
// should not warn about it being unused.
// If there are sub stmts in the compound stmt, take the type of the last one
// as the type of the stmtexpr.
QualType Ty = Context.VoidTy;
if (!Compound->body_empty())
if (Expr *LastExpr = dyn_cast<Expr>(Compound->body_back()))
Ty = LastExpr->getType();
return new StmtExpr(Compound, Ty, LPLoc, RPLoc);
}
Sema::ExprResult Sema::ParseTypesCompatibleExpr(SourceLocation BuiltinLoc,
TypeTy *arg1, TypeTy *arg2,
SourceLocation RPLoc) {
QualType argT1 = QualType::getFromOpaquePtr(arg1);
QualType argT2 = QualType::getFromOpaquePtr(arg2);
assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)");
return new TypesCompatibleExpr(Context.IntTy, BuiltinLoc, argT1, argT2, RPLoc);
}